The present disclosure relates to the control of subterranean water. Particularly, the present disclosure relates to a sump pump with an emergency backup system for use in a structure having a basement floor located below ground level, which must be kept free of the ingress of subterranean water.
In structures, such as homes, having basements or cellars which extend below ground level, it is imperative that the ingress of water be prevented so that the basement space may remain usable. To that end, structures typically have footing drains leading to a sump or other similar collection basin, from which water is removed via a sump pump. It is a common practice in many areas of the United States to provide the sump in the floor of the basement.
A typical sump pump is an AC motor driven pump which operates using line power. Generally, a liquid level sensing device is provided to energize the pump motor when water level in the sump reaches a predetermined height and to deenergize the motor when the level has dropped to a safe level. Various types of sensing devices have been used for this purpose including sensors, float operated switches and pressure responsive switches.
The need for the sump pump is often greatest when storms occur. Unfortunately, the sump pump may not function when needed in an emergency because of a power failure or it may fail to operate because, for example, the level sensing device fails to operate. There are other factors that may result in the sump pump becoming inoperative, such as corrosion of certain pump parts, or clogging of the sump pump as a result of debris accumulating in the sump. In an attempt to solve the problems associated with the sump pump during those periods when pumping is necessary, a well-provided home also has a battery-operated emergency or backup pump, so that pumping can continue to avoid basement flooding.
Such battery or DC motor driven pumps are typically mounted in the sumps alongside the primary pumps, with the DC motor circuit being activated in response to a power line failure. Alarms have been provided for giving a warning if the battery voltage falls below a predetermined level. Unfortunately, these auxiliary DC systems have left much to be desired in preventing flooding due to AC motor driven pump failure. By way of example, since the battery operated pumps are rarely used, they sometimes are inoperative when their use is required. This may occur because the battery is incapable of supplying the power necessary to drive the pump. Although the static battery voltage may appear to be satisfactory, the initial current drain may reduce the battery voltage below the usable value.
Accordingly, the present disclosure provides a sump pump with an emergency backup system which overcomes certain difficulties with the prior art systems. The emergency backup system can be activated in response to power line failure, malfunctioning of the sump pump and/or the sump pump being overpowered by volume of water in the sump.